Efficient Full-Wave Method of Moments Analysis and Design Methodology for Radial Line Planar Antennas

An efficient full-wave MoM analysis and a design methodology for radial line planar antennas (RLPA) is presented. The feeding network of the antenna is solved by using the appropriate Green´s function defined for the problem. Filling of the Z-matrices is considerably simplified due to the analytical formulation of the MoM. Also, assumptions made on the minimum size of the coupling neighborhood for the feeding conductive probes in the radial line enabled significant time reduction of the time spent on the matrix inversion. Moreover, exploration of the RLPA symmetries leads to several improvements in the overall performance. The MoM results of the feeding network are combined with the results of the radiating elements for obtaining the performance of the feeding network under load conditions. It is shown that the radial position of the radiating elements in the RLPA resemble an equilateral triangular array grid. This observation enabled to perform the analysis of the array external mutual coupling effect using the equivalent “unit-cell” concept derived from an infinite phased array analysis. Comparison of the MoM results of the feeding network to CST commercial software show significant computational timesavings and the results are found to be in a good agreement.